The present invention relates to a method of simulating, when a chemical containing a pesticidal compound is used indoors, an indoor behavior of the pesticidal compound including an estimation method of estimating the indoor behavior of the compound and a safety evaluating method of evaluating its safety in human bodies by using the estimation method; and, in particular, to a method of simulating an indoor behavior of a pesticidal compound in the case where a chemical containing the pesticidal compound is residually sprayed, sprayed in an indoor space, heated to vaporize, or sprayed over the whole floor area.
Conventionally known is a fugaciousness (hereinafter referred to as Fugacity) model for simulating a behavior of a chemical material in global environment. The above-mentioned fugacity model utilizes Fugacity whose unit is an external force by which the chemical material escapes from one medium to another medium, i.e., pressure. For example, when the chemical material concentration differs between two media A and B, concentrations in the respective media are expressed by:
xe2x80x83NA/VA=fAZA
NB/VB=fBZB
wherein N is chemical mass, V is volume of medium, f is Fugacity, and Z is Fugacity capacity of medium.
Here, while the mass N changes over time according to transference and degradation of the chemical material between the media A and B; assuming that volume V and Fugacity capacity Z are constant, the above-mentioned two expressions are represented as:
(dfA/dt)VAZA=dNA/dt=xe2x88x92(Degradation)Axc2x1(Transference)AB
(dfB/dt)VBZB=dNB/dt=xe2x88x92(Degradation)Bxc2x1(Transference)AB
When Degradation and Transference in these two differential equations are given, unknown parameters fA and fB can be determined by calculation. When these parameters are respectively multiplied by Fugacity capacity ZA and ZB, the chemical material concentrations in the respective media in a specific period of time can be simulated.
As an apparatus for simulating a behavior of a chemical material, Japanese Patent Application Laid-Open No. 64-88811 discloses a configuration of closed-space simulator which can perform simulation in response to any capacity of closed space without actually constructing a closed space when evaluating temperature change of a specific gas component such as carbonic acid gas.
As a configuration for evaluating influence of a harmful material on human bodies, Japanese Patent Application Laid-Open No. 3-89146 discloses a configuration of percutaneous absorption evaluation apparatus employing a vertical type diffusion cell which is a system closer to a clinical state than is a parallel type cell, thereby being capable of simultaneously measuring, in real time, the process of a chemical being emitted from its base on the skin by optoacoustic measurement and the process of the chemical infiltrating through the skin by absorptiometry.
Also, Japanese Patent Application Laid-Open No. 7-218496 discloses a configuration of system which uses the fact that a dissolution parameter inherently existing in a chemical material and a logarithmic value of median lethal dose of the chemical material with respect to a mammal are in a specific correlation, estimating acute toxicity of the chemical material with respect to the mammal.
Further, simulations of indoor behavior of a pesticidal compound when insecticides are sprayed in an indoor space, electrically heated to vaporize in a room, and sprayed over the whole floor surface are respectively disclosed in Y. Matoba et al., xe2x80x9cA SIMULATION OF INSECTICIDES IN INDOOR AEROSOL SPACE SPRAYING,xe2x80x9d Chemosphere, Vol.26, No.6, pp. 1167-1186, 1993; Y. Matoba et al., xe2x80x9cINDOOR SIMULATION OF INSECTICIDES SUPPLIED WITH AN ELECTRIC VAPORIZER BY THE FUGACITY MODEL,xe2x80x9d Chemosphere, Vol.28, No.4, pp.767-786, 1994; and Y. Matoba et al., xe2x80x9cINDOOR SIMULATION OF INSECTICIDES IN BROADCAST SPRAYING,xe2x80x9d Chemosphere, Vol.30, No.2, pp. 345-365, 1995.
The above-mentioned simulation models, however, do not mention how to solve differential equations, and minute time units set when solving the differential equations are assumed to be constant. Theoretically, the smaller is the minute time unit, the longer becomes the calculation time; whereas the solution would not converge when the minute time unit is large. Accordingly, in the case where a differential equation containing a parameter which changes over time is to be solved, when the minute time unit is set to a constant value so that the solution does not diverge, there is a problem that the processing speed of a computer must be enhanced.
Also, the above-mentioned simulation models fail to mention any security with respect to human bodies.
In order to solve the above-mentioned conventional problems, it is an object of the present invention to provide a method of simulating an indoor behavior of a pesticidal compound, which can process simultaneous differential equations accurately in a short time by automatically setting a minute time unit.
In order to achieve the above-mentioned object, the method of simulating an indoor behavior of a pesticidal compound in accordance with the present invention comprises a step of dividing an indoor environment into predetermined media (constituents) and forming a differential equation concerning a fugacity of the compound in each of the media; a step of determining the fugacity of the compound in each of the media from the differential equation; a step of determining the indoor behavior of the compound from the fugacity of the compound in each of the media; and a step of changing, in response to a fluctuation in mass balance of the compound indoors, a minute time unit used when solving the differential equation.
As the indoor environment is divided into predetermined media, and exchanges of the chemical compound between the media and the like are taken into account, simulation results close to the actual behavior of the compound can be obtained, while the minute time unit can be set automatically in response to fluctuation in mass balance when solving simultaneous differential equations including a parameter which changes over time. Accordingly, when a computer processes the above-mentioned differential equation, accurate solutions can be obtained in a short time.
Preferably, the method of simulating an indoor behavior of a pesticidal compound in accordance with the present invention further comprises a step of evaluating safety of the compound with respect to a human body according to the indoor behavior of the compound.
As a consequence of this configuration, the safety of the pesticidal compound with respect to the human body can be evaluated accurately in a short time. Accordingly, when formulating a chemical such as insecticide including the above-mentioned compound, simulation can be easily repeated while changing conditions, thereby making it easier to formulate a chemical having a high safety conforming to the aimed object.
Further, the method of simulating an indoor behavior of a pesticidal compound in accordance with the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is residually sprayed; whereas the above-mentioned media are a spraying site, suspended particles which are divided into at least one kind according to size, indoor air, a floor, a wall, and a ceiling.
Preferably, in this case, the differential equation at the spraying site is a differential equation stating a relationship among temporal change of fugacity of the compound at the spraying site, temporal change in volume of the spraying site, amount of attachment of the suspended particles to the spraying site, amount of transference of the compound between the spraying site and another medium, and change in amount of degradation of the compound at the spraying site; the differential equation in the suspended particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the suspended particles, temporal change in volume of the suspended particles, amount of transference of the compound between the suspended particles and another medium, and change in amount of degradation of the compound in the suspended particles; the differential equation in the indoor air is a differential equation stating a relationship among temporal change of fugacity of the compound in the indoor air, amount of discharge of the compound outdoors, amount of transference of the compound between the indoor air and another medium, and change in amount of degradation of the compound in the indoor air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of attachment of the suspended particles to the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of attachment of the suspended particles to the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of attachment of the suspended particles to the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The method of simulating an indoor behavior of a pesticidal compound in accordance with the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is spatially sprayed; whereas the above-mentioned media are suspended particles which are divided into at least one kind according to size, indoor air, a floor, a wall, and a ceiling.
Preferably, in this case, the differential equation in the suspended particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the suspended particles, temporal change in volume of the suspended particles, amount of transference of the compound between the suspended particles and another medium, and change in amount of degradation of the compound in the suspended particles; the differential equation in the indoor air is a differential equation stating a relationship among temporal change of fugacity of the compound in the indoor air, amount of discharge of the compound outdoors, amount of transference of the compound between the indoor air and another medium, and change in amount of degradation of the compound in the indoor air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of attachment of the suspended particles to the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of attachment of the suspended particles to the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of attachment of the suspended particles to the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The method of simulating an indoor behavior of a pesticidal compound in accordance with the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is heated to vaporize; whereas the above-mentioned media are condensed particles which are divided into at least one kind according to generation and extinction, high-concentration air, medium-concentration air, low-concentration air, a floor, a wall, and a ceiling which is divided into at least one kind according to compound concentration.
Preferably, in this case, the differential equation in the condensed particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the condensed particles, temporal change in volume of the condensed particles, amount of transference of the compound between the condensed particles and another medium, and change in amount of degradation of the compound in the condensed particles; the differential equation in the high-concentration air is a differential equation stating a relationship among temporal change of fugacity of the compound in the high-concentration air, amount of discharge of the compound, amount of transference of the compound between the high-concentration air and another medium, and change in amount of degradation of the compound in the high-concentration air; the differential equation in the medium-concentration air is a differential equation stating a relationship among temporal change of fugacity of the compound in the medium-concentration air, amount of transference of the compound between the medium-concentration air and another medium, and change in amount of degradation of the compound in the medium-concentration air; the differential equation in the low-concentration air is a differential equation stating a relationship among temporal change of fugacity of the compound in the low-concentration air, amount of discharge of the compound outdoors, amount of transference of the compound between the low-concentration air and another medium, and change in amount of degradation of the compound in the low-concentration air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The method of simulating an indoor behavior of a pesticidal compound in accordance with the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is sprayed over the whole floor; whereas the above-mentioned media are suspended particles which are divided into at least one kind according to size, indoor air, a floor, a wall, and a ceiling.
Preferably, in this case, the differential equation in the suspended particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the suspended particles, temporal change in volume of the suspended particles, amount of transference of the compound between the suspended particles and another medium, and change in amount of degradation of the compound in the suspended particles; the differential equation in the indoor air is a differential equation stating a relationship among temporal change of fugacity of the compound in the indoor air, amount of discharge of the compound outdoors, amount of transference of the compound between the indoor air and another medium, and change in amount of degradation of the compound in the indoor air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of attachment of the suspended particles to the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of attachment of the suspended particles to the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of attachment of the suspended particles to the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The method of simulating an indoor behavior of a pesticidal compound in accordance with the present invention may be such that the floor is constituted by a rug having ears of fiber, whereas a space between the ears is added to the above-mentioned media.
Preferably, in this case, the differential equation in the space between the ears is a differential equation stating a relationship among temporal change of fugacity of the compound in the space between the ears, temporal change in volume of the solution containing the compound in the space between the ears, amount of attachment of the compound into the space portion between the ears by falling, amount of transference of the compound between the space portion between the ears and another medium, and change in amount of degradation of the compound in the space portion between the ears.
Even in the case where a rug having ears of fiber is spread on the floor, when the space between the ears is further added to the media, the behavior of the compound can be simulated accurately, thus allowing various kinds of simulations to be performed.
In order to achieve the above-mentioned object, the computer program product of the present invention is a computer program product to be used together with an information processing apparatus comprising input means for receiving a data input from outside, display means, and readout means for reading out information from a computer-usable storage medium; the computer program product comprising a computer-usable storage medium which has a program area for storing a program and has a computer-readable program materialized in the storage medium for causing, according to data input from the input means, the display means to display a result of simulation of an indoor behavior of a pesticidal compound; the computer program product comprising, in the program area, a program for dividing an indoor environment into predetermined media and forming a differential equation concerning a fugacity of the compound, a program for determining the fugacity of the compound in each of the media from the differential equation; a program for determining the indoor behavior of the compound from the fugacity of the compound in each of the media, and a program for changing, in response to a fluctuation in mass balance of the compound indoors, a minute time unit used when solving the differential equation.
As the indoor environment is divided into predetermined media, and exchanges of the chemical compound between the media and the like are taken into account, simulation results close to the actual behavior of the compound can be obtained, while the minute time unit can be set automatically in response to fluctuation in mass balance when solving simultaneous differential equations including a parameter which changes over time. Accordingly, when a computer processes the above-mentioned differential equation, accurate solutions can be obtained in a short time.
Preferably, the computer program product further comprises, in the program area, a program for evaluating safety of the compound with respect to a human body according to the indoor behavior of the compound.
As a consequence of this configuration, the safety of the pesticidal compound with respect to the human body can be evaluated accurately in a short time. Accordingly, when formulating a chemical such as insecticide including the above-mentioned compound, simulation can be easily repeated while changing conditions, thereby making it easier to formulate a chemical having a high safety conforming to the aimed object.
The computer program product of the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is residually sprayed; whereas the above-mentioned media are a spraying site, suspended particles which are divided into at least one kind according to size, indoor air, a floor, a wall, and a ceiling.
Preferably, in this case, the differential equation at the spraying site is a differential equation stating a relationship among temporal change of fugacity of the compound at the spraying site, temporal change in volume of the spraying site, amount of attachment of the suspended particles to the spraying site, amount of transference of the compound between the spraying site and another medium, and change in amount of degradation of the compound at the spraying site; the differential equation in the suspended particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the suspended particles, temporal change in volume of the suspended particles, amount of transference of the compound between the suspended particles and another medium, and change in amount of degradation of the compound in the suspended particles; the differential equation in the indoor air is a differential equation stating a relationship among temporal change of fugacity of the compound in the indoor air, amount of discharge of the compound outdoors, amount of transference of the compound between the indoor air and another medium, and change in amount of degradation of the compound in the indoor air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of attachment of the suspended particles to the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of attachment of the suspended particles to the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of attachment of the suspended particles to the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The computer program product of the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is spatially sprayed; whereas the above-mentioned media are suspended particles which are divided into at least one kind according to size, indoor air, a floor, a wall, and a ceiling.
Preferably, in this case, the differential equation in the suspended particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the suspended particles, temporal change in volume of the suspended particles, amount of transference of the compound between the suspended particles and another medium, and change in amount of degradation of the compound in the suspended particles; the differential equation in the indoor air is a differential equation stating a relationship among temporal change of fugacity of the compound in the indoor air, amount of discharge of the compound outdoors, amount of transference of the compound between the indoor air and another medium, and change in amount of degradation of the compound in the indoor air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of attachment of the suspended particles to the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of attachment of the suspended particles to the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of attachment of the suspended particles to the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The computer program product of the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is heated to vaporize; whereas the above-mentioned media are condensed particles which are divided into at least one kind according to generation and extinction, high-concentration air, medium-concentration air, low-concentration air, a floor, a wall, and a ceiling which is divided into at least one kind according to compound concentration.
Preferably, in this case, the differential equation in the condensed particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the condensed particles, temporal change in volume of the condensed particles, amount of transference of the compound between the condensed particles and another medium, and change in amount of degradation of the compound in the condensed particles; the differential equation in the high-concentration air is a differential equation stating a relationship among temporal change of fugacity of the compound in the high-concentration air, amount of discharge of the compound, amount of transference of the compound between the high-concentration air and another medium, and change in amount of degradation of the compound in the high-concentration air; the differential equation in the medium-concentration air is a differential equation stating a relationship among temporal change of fugacity of the compound in the medium-concentration air, amount of transference of the compound between the medium-concentration air and another medium, and change in amount of degradation of the compound in the medium-concentration air; the differential equation in the low-concentration air is a differential equation stating a relationship among temporal change of fugacity of the compound in the low-concentration air, amount of discharge of the compound outdoors, amount of transference of the compound between the low-concentration air and another medium, and change in amount of degradation of the compound in the low-concentration air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The computer program product of the present invention may be such that the above-mentioned compound is introduced into an indoor space as a solution containing the compound is sprayed over the whole floor; while the above-mentioned media are suspended particles which are divided into at least one kind according to size, indoor air, a floor, a wall, and a ceiling.
Preferably, in this case, the differential equation in the suspended particles is a differential equation stating a relationship among temporal change of fugacity of the compound in the suspended particles, temporal change in volume of the suspended particles, amount of transference of the compound between the suspended particles and another medium, and change in amount of degradation of the compound in the suspended particles; the differential equation in the indoor air is a differential equation stating a relationship among temporal change of fugacity of the compound in the indoor air, amount of discharge of the compound outdoors, amount of transference of the compound between the indoor air and another medium, and change in amount of degradation of the compound in the indoor air; the differential equation at the floor is a differential equation stating a relationship among temporal change of fugacity of the compound at the floor, temporal change in volume of the floor, amount of attachment of the suspended particles to the floor, amount of transference of the compound between the floor and another medium, and change in amount of degradation of the compound at the floor; the differential equation at the wall is a differential equation stating a relationship among temporal change of fugacity of the compound at the wall, temporal change in volume of the wall, amount of attachment of the suspended particles to the wall, amount of transference of the compound between the wall and another medium, and change in amount of degradation of the compound at the wall; and the differential equation at the ceiling is a differential equation stating a relationship among temporal change of fugacity of the compound at the ceiling, temporal change in volume of the ceiling, amount of attachment of the suspended particles to the ceiling, amount of transference of the compound between the ceiling and another medium, and change in amount of degradation of the compound at the ceiling.
The computer program product of the present invention may be such that the floor is constituted by a rug having ears of fiber, whereas a space between the ears is added to the above-mentioned media.
Preferably, in this case, the differential equation in the space between the ears is a differential equation stating a relationship among temporal change of fugacity of the compound in the space between the ears, temporal change in volume of the solution containing the compound in the space between the ears, amount of attachment of the compound into the space portion between the ears by falling, amount of transference of the compound between the space portion between the ears and another medium, and change in amount of degradation of the compound in the space portion between the ears.
Even in the case where a rug having ears of fiber is spread on the floor, when the space between the ears is further added to the media, the behavior of the compound can be simulated accurately, thus allowing various kinds of simulations to be performed.